Conveyor drive systems are found in a wide variety of industries, as they are an important part of materials handling in all types of manufacturing. Sprockets are an integral part of the conveyor drive system, and as such make up a large part of the prior art. One particular issue is the securement of the sprocket on to drive drum so as to control the movement of the conveyor belt. Another issue is the wear of the sprocket as a result of the continuous engagement maintained with the conveyor belt.
Prior art conveyor drive systems have been devised to address the aforenoted problems. For example, U.S. Patent application 2003/0144098 discloses a split sprocket assembly, related apparatus and a method of mounting a sprocket to a rotatable structure such as a drive or idler drum. The sprocket assembly is comprised of at least three sections or segments each of which is secured to the adjacent section by a fastener such as a tangentially-extending bolt and nut combination. The sprocket assembly includes a plurality of receivers each for receiving a key that corresponds to a keyway formed in the rotatable structure.
U.S. Pat. No. 5,934,447 issued Aug. 10, 1999 to Kanaris discloses a roller drive sprocket system in which a drive roller mounts sprockets for driving a belt, and having a general cylindrical drive drum, semi-cylindrical grooves formed axially along the surface of the drive drum, sprockets formed of plastic with drive teeth for driving a belt, cylindrical metal keys located in the sprockets, spaced radially the keys fitting in the semi-cylindrical grooves in the surface of the cylindrical drive drum, portions of the keys extending inwardly to inter-engage with the semi-cylindrical grooves. U.S. Pat. No. 5,934,447 does not disclose a contoured collar adapted to engage the outer surface of the drive drum at predetermined points and thereby form predefined gaps between the drive drum and the contoured collar.
Thus a key sprocket drive system for driving a conveyor belt which has improved securement of the sprocket to the drive drum, and has predefined gaps that allows for improved expansion coefficients for the overall system thereby reducing wear of the key sprocket system is desirable.